Posted by Very Confused :( on .
I don't understand how to work out this problem, non the less where to begin with any calculations. Help!!
Three of the strongest lines in the He+ ion spectrum are observed at the following wavelength:
(1) 121.57 nm
(2) 164.12 nm
(3) 468.90 nm
Find the quantum numbers of the initial and final states for the transitions that give rise to these three lines. Do this by calculating, the wavelengths of lines that can originate from transitions involving any two of the four lowest levels. When a calculated wavelength matches an observed one, write down nhi and nlo for that line. Continue until you have assigned all three of the lines.
(1) __________ > _________
(2) __________ > _________
(3) __________ > _________

Chemistry 
Anonymous,
34